Differential mechanism for cash registers and calculating machines



Feb. 17, 1931. BREITLlNG 1,792,569

DIFFERENTIAL MECHANISM FOR CASH REGISTERS AND CALCULATING MACHINES Filed Feb. 7, 1928 mini-" PatentedFeb. 17, 1931 UNITED sTAT s PATENT oEHc ERNST BBEITLING, F ESSEN, GERMANY, ASSIGNOR TO FRIED. KRU'P]?v AKTIENGESE'LIi- SCHAFT, 0F ESSEN-ON-THE-BUHR, GERMANY 7 v nrrrnnnn'rmr. mncnnnrsm non cAsn REGISTERS nnncnnoutnrrne'mcnmns Application filed February 7, 1928, Serial No. 252,597, and in Germany June 16,1927.

The invention relates to differential mecha- 14, are rockingly mounted on shaft 11." By I nisms intended for cash registers and calcumeans of bolts 15, 16 the differential memlatlng mach nes and belonglng to that type, ber 12- is rigidly connected to a segment in which a differentially actuated chlef mem 17 which co-operates by means of a nose her and a differentially actuated auxiliary member actuated complementarily thereto co-operate with a row of keys.

In machines of this type the revolution of the actuating motion, the amount of which is the same in every differential motion, into the differential amount and the complementary difierential amount is effected by means of a differential gear. In known mechanisms of this design the actuating motion is introduced by the planet wheelof this differential gear, the two sun wheels of the gear being moved in the same direction. This arrangement has the disadvantage that the two differentially actuated members are moved from the same side toward the stop face of the set key, unless areversing gear is interposed for one of these two differentially actuated members By this reversing gear the clearance of the mechanism is however increasedand the setting is made inaccurate.

Now the invention has for its object to obviate this drawback, which object is attained by having the differentially actuated chief member positively connected to one of the two sun wheels of the. differential gear, and the auxiliary differential member to the planet Wheel carrier or vice-versa, the actuating motion being introduced by the other sun wheel of the difierential gear.

In order that the invention may be more easily understood, a preferred embodiment of same is illustrated in the drawing which ac-- companies and forms part of this specification. In this drawing:

Figure 1 is a side elevation of the differential mechanism, the differentially actuated members of which are mounted for rocking motion, and

Figure 2 is a section on line 11-11 of Figure 1.

Referring to these figures, 11 denotes a shaftrelatively to which the keys 10 are arranged concentrically. The difi'rentiall actuated chief member, arm 12, and the di 'ferentially actuated auxiliary member, arm

19 with a zero stop pawl 20 influenced by the keys, "and is held\ in zero position if none of thekeys 10 has been depressed. On its opposite side the segment 17 ,carries a toothed arc 21in mesh with a pinion 23 loose on a shaft 22: Pinion 23 is rigidly connected to a bevel wheel 2 f that constitutes one of the sun Wheels of the dilferential gear, the other sun wheel of which is bevel wheel 25, see Figure 2, rigid on shaft 22. Both wheel 24 and wheel 25 are in mesh with the planet wheel of the differential gear, viz. bevel wheel 26 loosely rotatable on a journal 27 of the, planet wheel carrier '28. The

'latter is rotatably mounted on shaft 22 by a hub 29, Figure 2, and is rigidly connected to a, toothed segment 30 in mesh with a series of teeth 13 of the auxiliary differential-member 14:. Each of the members 12 and 14 has a nose 31, Figure 1, co-operating with the foot 32 of the key 10 just depressed.

In eachoperation of the machine the shaft 22 has imparted to it a partial to and fro rotation of equal amplitude. This rotation is transmitted by bevel wheel 25 to planet wheel 26 and by the latter to carrier 28 and bevel Wheel 24. When this takes place, said two latter element-s move opposite one another and rock, during the forward rotation of shaft 22,v the difierential members 12, 14; connected to them from both sides toward the foot 32 of the depressedkey, while they return them to initial position upon the shaft 22 turning backward, the planet wh eel 26 of thedifierential gear 24, 25, 26 rolling on bevel wheel 24 and imparting to the carrier 28 an angular velocity which is half that of the actuating wheel 25, if the differential member 12 is stopped. If, on the contrary, it is the auxiliary differential member 14 thatjs stopped, then the planet wheel 26 rotates on journal 27 which is then stationary, the same but oppositely directed rotation being imparted to bevel wheel 24, as that of the actuating wheel 25. L

In order to maintain the angular velocities of the differential members 12, 14; equal, this beingrequiredj to have equal totals of the diflerential path s .of thesefmembers in each differential operation of 'the machine, a cor- "res Qn'ding ratio of transmission is. provi ed between .'the=--d iiferentially actuated members and. the'difi'erential gear. 'In' the embodiment illustrated fthe' pitch circle diametenof thelseries of teeth 13 and 30 ,'are

equal tOLjOIlG another, :while the pitch circle diameter ofthe tbotlied arc 21 is double that ofthe toothed arc 23. y arrangingth'e difierential gear on a'separate shaft 22, a convenient lodgementof the transmission gear- 5 ing is pro vided and, besides, more room is obtainedto lodge the totalizers of the ma- .chine. 4 3

These totalizers 34 are mounted on swing frames v35 and co-operate by means of -inter- 0 mediate wheels 36, 37'with a common difi'erentially actuated wheel 38 rigid on bevel wheel 24. .As bevel wheel 24 is in positive connection with the differential member 12,

. the .idiflt'erential adjustment of the totalizers 5 takes place in accordance with the motion of this member 12. i

The described differential mechanism is further providedwith anarrangement intended to lock the chief diiferential member so 12 in adjusted position. To this end a catch 40, urged by a spring 39, is ivoted on pin 16.- The catch 40 co-operates y means of its V-shaped lateral lug 41 with a series of. stop teeth 42 arranged on a stationary partition 43.

35 Catch 40 has connected to it an arm 44 projecting into the path 'of an adjustable lug formed by the set screw 45 mounted on the auxiliary differential member 14.

. When in the differential motion of the 40 members 12 and 14 the lug 45 strikes arm 44,

which occurs, when the noses 31 are in immediate proximity of the foot of the depressed key, catch 40 is rocked against the action of spring 39, so that'its lateral lug 41 45 engagesthat space which is just opposite .to it of the stop teeth 42. In this manner the chief differential member 12 is exactly positioned in its differential position and locked therein. The advantage afforded by this arrangement resides in the fact, that the parts T in consideration may operate with a certain clearance and neednot to have dimensions of highest exactness. A set screw 46 arranged on the auxiliary differential member 14 serves to exactly adjust the differential memars in initial position.

. To position the type wheel and the indicating wheel in accordance with the intro- ..duced value, an arm 47 is rockingly mounted cul-on' shaft 11 beside the auxiliary differential .-T member'14, Figure 2. A lateral pin 48 .of 3111147 co-operates with correspondingly 'lshaped recesses 49 "of the; members 12 and 14, "Fi'guref -1.1 Ann 47 carries a series of teeth leads to the appurtenant indicating wheel (not shown), and helical teeth 52 in mesh with a helical wheel 54 fast on a shaft 53. The latter carries the type wheel (not shown) allotted to the respective order of the diiferential mechanism. This arrangement enables the type wheel and the indicating wheel to be immediately setfrom the old po 'sition-to the new one and to remain in this new position lnthe following state of rest of the machine, during which state the differ ential members 12, 14 are ininitial position.

' At the commencement of theoperation of the machine the lateral pin 48 is in a posi-. tion between the two recesses 49 correspondso ing to the adjustment of the indicating wheel and type wheel caused by the preceding op eration of the machine.

Now, when the two differential members 12, 14 are moved with their noses 31 in the described manner against the foot 32 of the depressed key-10, one of them takes with it the pin 48, until the latteris enclosed by the two recesses 49 in .a tong-like'manner at the end.

' of the adjusting motion and arrives opposite the depressed key. After the indicating wheel and type wheel have then been locked in any known manner in their new position and the selected totalizers have been thrown into gear, the-return rocking motion of shaft 22 takes place, whereby ,the differential members 12, 14 are returned toinitial position shown in Figure 1 and'the introduced value is trans- 4 mitted to the selected totalizers.

The arm 47 and the indicating wheels and type wheels positively connected thereto re-,- main in the adjusted position. If no key had been depressed in the respective order of the differential mechanism, the chief differential member 12 remainslocked in initial position by pawl 20, so that the eptire actuating motion of shaft 22 is transmitted to the auxiliary difi'erential member 14. In this case the indicating and type wheels are set to zero, while apositioning of the respective counting wheel does not take place.

, What I claim and desire to secure ters Patent, is

1. In a machine of the class described the combination with a pair of complementarily movable differential members pivotally mounted on a shaft, a driving member, a planet gear mechanism adapted to resolve the movement of thedriving member into two complementary amounts destined for said differential members, respectively, said planet, gear mechanism being pivotally mounted on a second shaft extending in parallel to said first-named shaft.

2. In amachine of the class described the combination according to claim 8, in which said connections consist of gearings on said last named sun wheel and said carrier, the ratio' of transmission of said gearings being so chosen as to produce an equal angular veby Let locity of each difierential member with a' certain driving movement of the driving shaft.

3. In a machine of the class described the 5,combination with a pair of complementarily movabledifierential members, a single device for adusting and lockin both difierential members in adusted position, connections arranged between said device and the difierential members and adapted to cause said dewith said stop teeth upon the differential members being about to reach their adjusted position.

5. In a machine of the class described, a pair of complementarily movable difierential members, an element mounted for bodily and rotational movement, positive connections whereby the bodily movement of said element is transmitted to one ,of said differential members, positive connections whereby the rotational movement of said element is transmitted to the other of said differential members, a driving member for said element hav-' ing a constant extent of motion for each operation of the machine, said element adapted to resolve said constant extent of motion of said driving member into variable but complementary bodily and rotational movements. I

' 6. In a machine of the class described, a pair of complementarily movable difierential members, an element mounted for bodily and other sun wheel and one of said difierential members, and connections for transmitting bodily movements of said planet wheel to the other 'difierential member.

8. In a machine of the class described, the combination of a shaft, a pair of complementarily movable differential members rotatably mounted on said shaft, a driving shaft, a planet gear mechanism-mounted on said driving shaft comprisin two sun wheels and a lanet wheel, one 0 said sun wheels being xed to said driv in shaft, positive-connections between the ot er sun wheel and one of said difi'erential members, a carrier on which said planet wheel is mounted, and positive connections between said carrier and the other differential member.

The foregoing specification si ed at Cologne, Germany, this'19th day of annary,

ERNST -BREITLING.

I rotational movement, positive connections whereby the bodily movement of said element is transmitted to one of said differential members, positive connections whereby the rotational movement of said element is transmit-.

ted to the"other of said differential members,

i a driving member having a constant extent of motion adapted to directly impart said rotational movement to said element, said element adapted to resolve the,constant extent of motion of said driving member into variable but complementary bodily and rotational movements.

7., In a machine of the class described, a pair of difierential members, a driving mem er having a constant extent of motion, and mechanism for resolving the motion of said driving member into variable but complementary motions of said difierential mem-- bers, comprisin planetary gearin consisting of two sunw eels and aplanetw eel, connections between one sun wheel and said driving member, connections between the 

